Side loader attachment for industrial lift trucks



8. l. ULINSKI May 24, 195 5 SIDE LOADER ATTAGBMENT FOR INDUSTRIAL LIFTTRUCKS 3 Sheets-Sheet 1 Filed Sept 5 INVENTOR d m BY ATTORNEY y 4, 1955a. ULINSKI 2,709,017

SIDE LOADER ATTACHMENT FOR INDUSTRIAL LIFT TRUCKS Filed Sept. 5 1951 3Sheets-Sheet 2 INVENTOR 'AT-TORNEY ULINSKI May 24, 1955 sIpE 1.0mmATTACl-MENTFOR mnus'mm, 1.1m- 'mucxs Filed Sept. 5, 1951 3 Sheets-Sheet3 111:: will INVENTOR 4 ATTORNEY United States Patent SIDE LOADERATTACHMENT FOR INDUSTRIAL LIFT TRUCKS Bronislaus I. Ulinski, Chicago,IlL, assignor to The Yale & Towne Manufacturing Company, Stamford,Conn., a corporation of Connecticut Application September 5, 1951,Serial No. 245,164

Claims. (Cl. 214-671) This invention relates to industrial lift trucksof the class employed for transporting, stacking, and tiering boxes,bales, loaded pallets and other articles, and more particularly tomechanism that will enable trucks to manipulate loads at the sidethereof.

It has been found desirable, in trucks of this general class, to mountthe load lifting members at one end of the truck, the engagement ofthese members with theload being brought about through steeredmanipulation of the truck. Therefore, when a truck of this class is usedin a warehouse, for example, it has heretofore been necessary tosacrifice a part of the storage space in order to provide a sufficientlywide aisle to allow the truck room in which to turn so as to bring itsload lifting member into engagement with a load at one side of theaisle. It is the purpose of my invention to provide a truck constructionthat will extend the zone in which loads may be effectively handled by atruck of this class to include positions offset from the line of travelof the truck, whereby to reduce to a minimum the space that is requiredfor maneuvering the truck itself.

As one feature of my invention, I so mount the load lifting member thatit may be turned and thereby directed to engage a load that may be inany one of a number of different positions relatively to the truck.Thus, where the load lifting member is one or more forks, for example,the forks may be directed forwardly to lift a load in the path of thetruck, as is conventional, or the forks may be directed through theirturning movement toward a load that is located entirely at one side ofthe truck. In the latter case, the forks are placed in liftingrelationship to the load through means that move the forks relatively tothe truck, this movement preferably occurring as a thrusting movement ofthe forks in the direction of their length in any of their particularrotated positions. The rotating and the thrusting movements of the forksserve not only in engaging and releasing the load, but also in rotatingand moving the load while it is carried by the forks.

As another feature of my invention, the lifting and lowering movement ofthe forks may occur in any rotated or laterally moved position that theymay assume relatively to the truck, and this lifting and loweringmovement preferably is contributed through the usual lifting carriagewith which lift trucks are equipped.

A further feature of my invention resides in the means whereby theturning of the load lifting member occurs as a pivotal movement centeredat the laterally retracted position of the forks or load lifting member.Since the retracted position of the load lifting member is preferablylocated on the longitudinal axis of the truck, the load lifting membermay therefore be rotated to direct it toward a load disposed at the sideof an aisle having a width that is little more than sufficient to permitthe passage of the truck. This arrangement is attained by supporting theload lifting member through a pivotal meansthat is located at theretracted position of the load ice lifting member, and that is carriedpreferably by an overhanging member mounted on the truck.

I have thus outlined rather broadly the more important features of myinvention in order that the detailed description thereof that followsmay be better understood, and in order that my contribution to the artmay be better appreciated. There are, of course, additional features ofmy invention that will be described hereinafter, and which will form thesubject of the claims appended hereto. Those skilled in the art willappreciate that the conception on which my disclosure is based mayreadily be utilized as a basis for the designing of other structures forcarrying out the several purposes of my invention. It is important,therefore, that the claims to be granted me shall be of sufficientbreadth to prevent the appropriation of my invention by those skilled inthe art.

Referring now to the drawings:

Fig. 1 is a plan view of the preferred form of my novel side loadershowing the forks rotated and thrust laterally of the truck for pickingup a load at the side of an aisle, and also showing in broken lines theforks retracted to withdraw the load to a position in the aisle andaligned with the truck.

Fig. 2 is an end view of the truck of Fig. 1.

Fig. 3 is a side elevation with the forks in a forward position, and thedotted lines showing the forks thrust forwardly.

Pig. 4 is a cross sectional view on lines 4-4 of Figs. 3 and 5, showingthe construction of a hydraulic motor that I have provided as an exampleof a means for rotating the forks.

Fig. 5 is a cross sectional view taken on line 5-5 of Fig. 4, showingthe motor and the bearing that provides the pivotal support.

Fig. 6 is a side view of a part of my invention showing the scissorslegs for supporting and moving the forks relatively to the rotatingsupport member.

Fig. 7 is a cross-sectional view taken on the line 7-7 of Fig. 6,showing the construction of a hydraulic motor as an example of a meanscontributing the lateral thrusting movement of the forks.

Figs. 8, 9 and 10 are partial sectional views taken respectively on thelines 88, 99 and 1010 in Fig. 6, showing the end connections of thescissors legs.

Fig. 11 is a diagram showing the arrangement of the conduits wherebyfluid is supplied for operating the motors.

In the preferred form of the invention shown in the drawings, I utilizea lift truck T of a known type for carrying and operating my novel sideloader indicated generally by the numeral 10. As is customary in trucksof'this general class, the truck T carries at its front end a pair ofprimary uprights 11 and a pair of secondary uprights 12 that in turncarry a lifting carriage 13. The lifting carriage 13 is guided forvertical movement upon the secondary uprights 12, these secondaryuprights being vertically movable in turn upon the primary uprights 11so as to extend the vertical range of movement of the lifting carriage,the vertical movement being under the control of the operator through ameans that may take the form of a hydraulic ram 14 (Fig. 2).

The lifting carriage13of the truck T is equipped with the conventionalvertical front plate 15 that serves as a means whereby the load engagingmember is attached to the truck for vertical movement upon the truck.The load engaging member in this application is my new side loader 10and carries a pair of lifting forks 16 forming here the particular loadengaging or contacting parts. It will be understood that if the lifttruck T were to be utilized in a conventional manner, the forks 16 wouldbe mounted directly upon the vertical front plate 15, and these forkswould be thrust into lifting'relation to a load by driving the truck Tin a direction against the load. While this conventional mode ofoperation has provided very efficient handling of loads, it is quiteobvious that a truck could not thereby effectively engage loads offsetfrom its line of travel. It will be seen by reference to Fig. l, forexample, that when the lift truck T is operated in a relatively narrowaisle, the truck cannot through bodily turning movement bring the forks16 into effective engagement with a load A at the side of the aisle. Bythe provision of my novel side loader 10, I have contributed a truckadapted for handling not only loads disposed in the line of travel ofthe truck, but also loads offset from any particular line of travel.

Referring now to Figs. 1, 2, and 3, the attachment comprises a rigidbearing beam 17 that is adapted to be mounted on the front plate of thelifting carriage l3, and that has the shape of an inverted i. so as toproject, forwardly of the truck at a level considerably above thelifting carriage. It will be noted at this point that the bearing beam17 projects forwardly from the truck a distance sufiicient to locate itsouter end in a position centered or approximately centered above thepair of forks 16 when the latter are in their retracted position, aswill be further explained hereinafter.

Supported in a depending position below the projecting portion of thebearing beam 17 is a rigid load carrier 18 also in the shape of aninverted L, and mounted for rota tion about a vertical axis by a ballbearing 19 (Fig. 5) at the outer end of the bearing beam 17. The outerrace of ball bearing 19 is held in a recess in the underside of bearingbeam 17 by a retaining ring 20, while the inner race carries the loadcarrier 18 through a ring 21. Since the pair of forks 16 is carried bythe load carrier 13, these forks will obviously rotate in a horizontalplane on bearing 19 so that they may be directed toward loads disposedin different positions relatively to the truck T.

The forks 16 may, of course, be engaged in a conventional manner with aload by movement of the truck toward the load. In order that the forks16 may also be brought into lifting engagement with a load withoutmovement of the truck, and particularly with a load A that is offsetfrom the line of travel, as illustrated in Fig. l, I mount the forks 16through a linkage means that provides for longitudinal thrustingmovement of the forks relatively to the load carrier 18. This linkagemeans utilizes scissors legs formed by rigid pairs of parallel members22,

23, best seen in Figs. 6 to 10, connected at their intersections by apivot shaft 24. As may be seen in Fig. 7, flanged bushings are splinedon the ends of the pivot shaft 24 and attached to the outer scissors legmembers 22 by screws 26, while the inner scissors leg members 23 arepivotally mounted on the bushings 25 whereby to swing relatively to themembers 22.

The rear ends of the members 22, 23, that make up the scissors legs aremounted upon a pair of opposed channel members 27 in the vertical leg ofthe load carrier 18, and the forward ends of the members 22, 23, areconnected to a similar pair of opposed channel members 28 forming thesides of a vertical frame 29 that carries the forks 16. The upper endsof the scissors leg members 22, 23, have rollers 30, 31, engaged in thepairs of channel members 27, 28, thereby maintaining the frame 29vertical as it is projected and retracted relatively to the vertical legof the load carrier 18, and the lower ends of the scissors leg members22, 23, are connected to the lower portions of the channel members 27,28, by pivot pins 32, 33, thereby supporting the vertical frame 29, at aconstant elevation as it moves relatively to the load carrier 18. Ofcourse, it is desirable that the scissors legs be capable of retractionto an extreme degree, and therefore the scissors leg members 23 haveuninterrupted swinging movement in planes between the members 22, andall of these leg members may be retracted to a position almost entirelybetween the channel members 27 of the load carrier 18, as will beapparent from Fig. 3.

As a means for mounting the forks 16, the vertical frame 29 is equippedwith a vertical front plate 34 that preferably is substantiallyidentical to the front plate 15 on the lifting carriage 13, therebypermitting the use in the attachment 10 of forks or other load liftingmembers that would otherwise be mounted on the lifting carriage 13. -Itwill be found convenient to so mount the front plate 34 in theattachment 10 that it will be disposed at the same elevation as thefront plate 15, and because the attachment 10 provides extremeretraction of the vertical frame member 22, the front plate 34 mayoccupy a retracted position that is but a short distance forwardly ofthe front plate 15. The forks 16 may therefore be supported in verynearly the same position they would occupy if mounted conventionallyupon the lifting carriage 13, thus permitting the truck T to beoperated, when desired, in substantially a conventional manner.

Returning now to the arrangement whereby the attachmeat 10 providesrotation about a vertical axis, it will be noted that the point ofpivotal support as represented by the ball bearing assembly 19 iscentered above the forks 16 when the latter are supported in theirretracted position by the front plate 34. Although it is not necessarythat this centering be precise, and it is not my intention to so limitthe invention, this arrangement is nevertheless of importance since itpermits the pair of forks 16 to pivot substantially in situ.Consequently, the rotation of the forks, with or without a load thereon,requires little more space than is required for the passage of thetruck, and permits very successful operation in a narrow aisle. Thus,whether the forks are loaded or empty, they may be rotated in the aisleso as to be directed through their thrusting movement either forwardlyof the truck or in a sideward direction. It will be obvious also thatthe stresses in the ball bearing assembly 19 will be somewhat reduced bythis arrangement, in view of the fact that a load may be carried by theforks 16 in their retracted position with a minimum of eccentric forceupon the bearing 19.

It will be understood that the vertical lifting movement of the forks 16will be brought about by the vertical movement of the lifting carriage13 upon the truck uprights 12, under the control of the truck operator.The lifting carriage 13 lifts the entire attachment 10, and

. the lifting movement therefore occurs without reference to therotating or lateral movements of the forks or to the positions in whichthe forks may he placed by such movements.

The particular construction of the means whereby rotating and lateralmovement is imparted to the forks is not important to my invention, andany suitable hy draulic, electric, or even manual means may be employedfor this purpose, such means preferably being subicct to close control.by the truck operator. 1 have shown in the drawing one form of operatingmeans whereby the forks may be rotated and also a similar means foreffecting the lateral movements of the forks. Thus, referringparticularly to Figs. 4 and 5, I provide coaxially within the ballbearing 19, an upper rotary hydraulic ram 35 that is adapted to turn theload carrier 18 relatively to the bearing beam 17. This ram has anannular core 36 that is fixed relatively to the bearing beam 17, and arotatable cylinder 37 that embraces this core and is keyed to the loadcarrier 18 through screws 38 (Fig. 4). A piston means 39 is attached tothe inner surface of the cylinder 37 so as to move in a circumferentialchannel 40 in the core. A closure 41 fixed on the core 36 within thechannel 40 divides the channel so that fluid pressure applied at eitherside of said closure will move the piston 39 in either direction in thechannel, and thereby will rotate the cylinder 37 and the load carrier 18to which it is keyed.

In order to move the forks 1 6 laterally, I may provide a lowerhydraulic ram 42 on the pivot shaft 24 at the intersection of thescissors legs 22 and 23. This ram S is best seen in Fig. 7 and,excepting for the m'arir'ie'r in which it is mounted, is similar to theupper ram 35 I have described for rotating the forks. In the ram 42, thesplined shaft 24 passes through the center of the annular core 36 andhas an integral flange 43 keyed to said core through screws 44. Thescissors legs 23 are attached, on

the other hand, to the cylinder 37 of the ram 42 by screws 45. Theoperation of this lower ram thereby causes the scissor legs 23 to swingrelatively to the legs 22 and projects or retracts the forks 16 with thevertical frame 29, as the case may be.

As a means through which fluid under pressure may be transmitted to andfrom the lower ram 42, I have shown in Figs. 5 and 11, a pair of upperand lower swivel joint members 46 and 47 disposed within the annular lcore 36 of the upper ram 35. The upper joint member 46 is non-rotatingrelatively to the bearing beam 17 and has fluid under pressure suppliedthereto through conduits 48 (Fig. 11). The fluid passes to or from theseconduits through circular grooves 49 in the upper joint member 46, thesegrooves being always in registry with ports in the lower joint member 47that rotates with the load carrier 18. These ports are connected to thelower ram through conduits 5i) as will be understood by those acquaintedwith the art.

It is believed that the operation of my novel side loader will beapparent from the foregoing description. Through my invention I haveextended the effective load handling zone of a lift truck from an areain front of the truck to areas laterally offset from the truck. Thetruck is therefore capable of handling efliciently a load that is in anyposition that can be approached by the truck without regard to the angleof approach. The invention also affords independent control of thelifting, rotating and lateral movements of the load lifting member sothat any of these movements may be accomplished at any stage of theother movements. The operator has at his disposal, therefore, a ,meanswhereby a substantially universal movement may be imparted to the loadlifting member or forks, whether they are loaded or empty. While I havedescribed as embodied in my invention an attachment to be applied to alift truck, it will be understood that the invention may, through theexercise of ordinary skill, be embodied to advantage in a unitary truck.Further, it is within the scope of the invention to embody a liftingmeans in the attachment whereby to lift the forks relatively to thatpart of the attachment which is secured to the truck. Such a liftingmeans could be provided without difficulty in the vertical frame 29 forexample, or in the bearing beam 17 or load carrier 18, and would renderthe attachment effective when applied to a tractor or non-lifting truck.

I now claim:

1. In a combination of the class described, a truck, uprights on saidtruck, a lifting carriage mounted for vertical movement on saiduprights, a bearing beam mounted on said lifting carriage whereby tomove vertically with said lifting carriage, a load carrier mounted onsaid bearing beam for rotation about a vertical axis spaced outwardlyfrom said truck, a load lifting member, scissors legs mounting said loadlifting member on said load carrier for lateral movement relatively tosaid vertical axis in various directions controlled by therotated position of said load carrier on said bearing beam, means moving said loadlifting member through said scissors legs whereby to engage a loadoffset from said vertical axis and to move a load carried by said loadlifting member relatively to said vertical axis, and means moving saidlifting carriage vertically on said uprights whereby said load liftingmember through its vertical movement Will engage loads attditferentlevels and will move loads laterally at different levels in any rotatedposition to which said load lifting member is turned relatively to saidtruck.

2. In a truck of the class described, a truck body hav- Cit 8 inguprights, a carriage moving vertically on said uprights, a bearing beammounted on the vertically moving carriage and extending longitudinallytherefrom, a rotating load carrier having a base portion, means mountingsaid load carrier for rotation on said bearing beam on a vertical axisspaced longitudinally from said truck body with said base portion inspaced relation to said axis in all rotated positions of the loadcarrier, a load lifter having an inner part, means mounting said loadlifter on the base portion of said rotating load carrier for lateralmovement toward and away from said base portion with the inner part ofsaid load lifter moving from a position displaced from one side of saidvertical axis to a position similarly displaced on the other side ofsaid vertical axis, and said base portion lying entirely on the side ofsaid axis opposed to that side to which the inner part of said loadlifter is moved when said load lifter moves away from said base portion.

3. In a truck of the class described, a truck body, a bearing beam,means mounting said bearing beam on said truck body to extendlongitudinally therefrom, a rotating load carrier having a vertical baseportion and a horizontal portion, means mounting the horizontal portionof said load carrier for rotation on said bearing beam on a verticalaxis spaced longitudinally of said truck body with said base portionalways in spaced relation to said axis, a load lifter having an innerpart, means mounting said load lifter on the base portion of saidrotating load carrier for lateral movement toward and away from saidbase portion with the inner part of said load lifter moving from aposition displaced to one side of said vertical axis to a positionsimilarly displaced on the other side of said vertical axis, and saidvertical base portion lying entirely on the side of said axis to whichthe inner part of said load lifter always moves when said load liftermoves toward said base portion.

4. In a truck of the class described, a truck body, a bearing beam,means mounting said bearing beam on said truck body to extendlongitudinally therefrom, a rotating load carrier having a horizontalportion adapted to lie in juxtaposed relation to said beam and avertical base portion, means mounting the horizontal portion of saidload carrier for rotation on said bearing beam on a vertical axis spacedlongitudinally from said truck body whereby in one rotated position ofsaid rotating load carrier to bring said vertical base portion injuxtaposed relation to the body of said truck, a load lifter having aninner part, means mounting said load lifter on the base portion of saidrotating load carrier for lateral movement of its inner part from aposition juxtaposed to said base portion and displaced to one side ofsaid vertical axis when said base portion is in juxtaposition to saidtruck body to a position similarly displaced on the other side of saidvertical axis.

5. In a truck of the class described, a truck body, a bearing beam,means mounting said bearing beam on said truck body to extendlongitudinally therefrom leaving a considerable open space between saidbeam and the ground on which the truck moves, an inverted L-shapedrotating load carrier having a horizontal bearing portion and a verticalbase portion, means mounting the horizontal portion of said load carrierfor rotation on said bearing beam on a vertical axis spacedlongitudinally from said truck with said vertical base portion always inspaced relation to said vertical axis in all rotated positions of saidrotating load carrier whereby in one rotated position of said rotatingload carrier to bring said vertical base portion in juxtaposed relationto the body of said truck, a load lifter having an inner part, meansmounting said load lifter on said base portion for lateral movement ofits inner part from a position adjacent to said vertical portion anddisplaced to one side of said vertical axis to a position similarlydisplaced on the other side of said vertical axis, and said liftermounting means lying entirely on one side of said axis.

6 In a combination of the class described, a truck having uprights, acarriage moving vertically on said uprights, a bearing beam mounted onsaid vertically moving carriagc, said beam extending longitudinally fromthe carriage and leaving a considerable open space between said beam andthe ground in all vertical positions of the carriage on the uprights, aload carrier having a horizontal p r ion in iu tap rel t on o a d beamle sa pa s stan al y open, mea m nti said e d c rrier through itshorizontal portion for rotation on said bearing beam on a vertical axisspaced longitudinally om aid ck a oa l te a in n inne end p a downwardlyextending portion on said load carrier spaced from said vertical axis,means mounting said load lifter on sai dow a d y endi p o o ai a arrierfor movement of its inner end part to and from a PQSiIlD iuxtapc ed d on y extending P tion, and means for moving said load lifter on itsmounting means i a y otat posi ion o a d oa carrier to and from the sideof said vertical axis opposed to that side on which said downwardlyextending portion lies.

7. In combination of the class described, truck having uprights, acarriage moving vertically on uprights, a bearing beam mounted on thevertically moving carriage and extending longitudinally therefromleaving a considerable open space between said beam and the ground onwhich said truck moves, a load carrier having a narrow horizontalportion in juxtaposed relation to said beam leaving said spacesubstantially open, means mounting said load carrier through itshorizontal portion for rotation on said bearing beam on a vertical axisspaced longitudinally from said truck, a load lifter having an inner endpart, a downwardly extending portion on said load carrier spaced fromsaid vertical axis in all rotated positions of said carrier, meansmounting said load lifter on said downwardly extending portion of saidload carrier for movement from a position in said vertical axis with itsinner end part juxtaposed to said downwardly extending portion to aposition away from said vertical axis and said downwardly extendingportion, and means for moving said load lifter on its mounting means inany rotated position of said load carrier.

8. In a truck of the class described, a truck body having uprights, acarriage moving vertically on said uprights, a bearing beam mounted onthe vertically moving carriage and extending longitudinally from saidcarriage, a rotating load carrier having a base portion, means mountingsaid load carrier for rotation on said bearing beam on a vertical axisspaced longitudinally from said truck body with said base portion inspaced relation to said axis in all roto a position similarly displacedon the other side of said vertical axis, and said base portion lyingentirely on the side of said axis opposed to that side to which saidfork is moved relatively to said base portion.

9.. In a combination of the class described, a truck,

a bearing beam extending longitudinally from said truck leaving aconsiderable open space between said beam and the ground on which saidtruck moves, means mounting said bearing beam for vertical movement onsaid truck, a load carrier having a horizontal portion in juxtaposedrelation to said beam leaving said space substantially open, meansmounting said load carrier through said horizontal portion for rotationon said bearing beam on a vertical axis spaced longitudinally from saidtruck, a fork having a rear end, a downwardly extending portion on saidload carrier spaced from said vertical axis, means mounting said fork.on said downwardly extending portion of said load carrier for movementof its rear end to and from a position juxtaposed to said downwardlyextending portion, and means for moving said fork on its mounting meansto and from the side of said vertical axis opposed to that side on whichsaid downwardly extending portion lies.

10. In a combination of the class described, a trunk, no rights on saidtruck, a lifting carriage mounted for vertical movement on saiduprights, a bearing beam mounted on said lifting carriage whereby tomove vertically with said lifting carriage, a load carrier mounted onsaid hearing beam for rotation about a vertical axis spaced outwardlyfrom said truck, a load lifting member, means mounting said load liftingmember on said load carrier for lateral movement relatively to saidvertical axis in various directions controlled by the rotated positionof said load carrier on said bearing beam, means moving said loadlifting member on its mounting means relatively to said load carrierwhereby to engage a load offset from said vertical axis and to move aload carried by said load lifting member relatively to said verticalaxis, and means moving said lifting carriage vertically on said uprightswhereby said load lifting member through its vertical movement willengage loads at different levels and will move loads laterally atdifferent levels in any rotated position to which said load liftingmember is turned relatively to said truck.

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